CHRISTOPHER NOLAN’S “Dunkirk” stormed the box office with a better-than-expected US$50.5 million domestic debut, the best opening in recent memory for a World War II film and a testament to the Nolan brand.

Still, “Dunkirk” will need sizeable staying power in order to recoup a net production budget of US$100 million and a major marketing spend. Nolan made the movie for Warner Bros., his longtime partner and home of his blockbuster “Dark Knight” trilogy. “Dunkirk,” playing in 3,720 locations, no doubt benefited from a major push in Imax theaters, which delivered US$11.7 million, or 23 percent of the total gross.

Heading into the weekend, many box-office pundits predicted that “Dunkirk” would have trouble crossing US$40 million, considering its subject matter. They readily admit they were wrong. In addition to strong reviews, “Dunkirk” earned an A- CinemaScore from audiences. It skewed heavily male (60 percent), while 76 percent of all ticket buyers were over the age of 25.

“Dunkirk” opened on par with Nolan’s last film, “Interstellar,” which launched to nearly US$50 million over the long Thanksgiving holiday in 2014, including US$47.5 million for the three-day weekend.

Recounting one of World War II’s most famous battles, “Dunkirk” stars Fionn Whitehead, Mark Rylance, Kenneth Branagh, Cillian Murphy, Tom Hardy, Jack Lowden — and Harry Styles from One Direction, who makes his acting debut in the movie, much to the delight of fans, who made their presence known at the film’s London and New York premieres.

Among other relatively recent World War II films, Angelina Jolie’s “Unbroken” debuted to US$30.6 million in December 2014, while “Fury” launched to US$23.7 million in November of that same year. Last year, Mel Gibson’s “Hacksaw Ridge” bowed to US$15.2 million.

To this day, Steven Spielberg’s “Saving Private Ryan” (1998) remains the top-grossing World War II movie of all time domestically, earning US$216.5 million (or US$404.4 million when adjusting for inflation). The film opened to US$31 million (or US$57.6 million when accounting for inflation).

Overseas, “Dunkirk” is also making a major push.

Elsewhere at the North American box office, Universal’s “Girls Trip” broke the R-rated comedy curse in debuting to US$30.4 million from 2,591 theaters. That’s the best showing so far this year for the genre, and helps to make up for summer flops “Rough Night” and “The House.” Like “Dunkirk,” “Girls Trip” came in ahead of expectations.

The comedy was made for roughly US$20 million, a modest number compared to “Dunkirk” and the weekend’s third new nationwide release, French filmmaker Luc Besson’s “Valerian and the City of Thousand Planets.”

“Valerian,” a sci-fi epic costing US$180 million, crash-landed in the U.S. with US$17 million from 3,553 theaters. STX Entertainment is releasing the movie in the U.S. via its partnership with Besson’s EuropaCorp, but doesn’t have any money in the film. Nor did STX pay for marketing, according to insiders.

Receiving a B- CinemaScore, “Valerian” is based on the French graphic novel series and stars Dane DeHaan and Cara Delevingne as celestial cops who must travel through space and time in order to save the universe.